Quantitative Aptitude - Arithmetic Ability Questions

If α + β = 90° and α:β = 2:1, then the ratio of cosα to cosβ is

A book is sold at three successive discounts of 20%, 20% and 10%. What is the net discount (in percentage)?

The circumferences of two circles are touching externally. The distance between their centres is 12 cm. The radius of one circle is 7 cm. Find the diameter(in cm) of the other circle.

A wholesaler sells a watch to a retailer at a gain of 20% and the retailer sells it to a customer at a loss of 10%. If the customer pays Rs 874.8, what had it cost the wholesaler?

A can do a work in 20 days and B in 10 days. If they work on it together for 5 days, then what fraction of work is left.

The percent profit made when an article is sold for Rs. 78 is twice as much as when it is sold for Rs. 69, the cost price of the article is?

The marked price of an article is Rs 960 and it is sold at a discount of Rs 192. What is the discount percentage?

What is 0.53 + 0.53equal to ?